Charges Dropped Against Ricin-Letter Suspect as Cops Search New Suspect

"The big part that we took from the testimony is that thorough and complete searches were done of Mr. Curtis's residence, his former wife's residence, as well as his vehicle -- the vehicle he was driving at the time of the stop -- and there was nothing found on anything that linked him to these crimes."

Curtis told the court Monday that he would no longer use computers or Facebook and that he would no longer engage in activism, believing his activities online led to his arrest.

According to the criminal complaint lodged against him, the FBI quickly traced the tainted letters to Curtis's house by matching the signature on the letters, which read "This is KC and I approve this message," to a number of other letters and Internet postings Curtis had written.

The letter was mailed from Memphis, Tenn., about 100 miles north of Curtis's home, according to the charging documents.